package com.ustb.shellbox.shelllife.customview;

import android.support.v4.view.ViewPager;
import android.view.View;

/**
 * Created by 37266 on 2017/3/22.
 */

public class DepthPageTransformer implements ViewPager.PageTransformer {
    private static final float MIN_SCALE=0.75f;
    @Override
    public void transformPage(View page, float position) {
        int pageWidth =page.getWidth();
        if(position<-1){//[-Infinity,-1)  
//            This page is way off-screen to the left.  
        page.setAlpha(0);
        }else if(position<=0){// [-1,0]//  
            // Use the default slide transition when moving to the left page  
            page.setAlpha(1);
            page.setTranslationX(0);
            page.setScaleX(1);
            page.setScaleY(1);
            }else if(position<=1){// (0,1]  
            // Fade the page out.  
            page.setAlpha(1-position);
// Counteract the default slide transition  
            page.setTranslationX(pageWidth*-position);
// Scale the page down (between MIN_SCALE and 1)  
            float scaleFactor=MIN_SCALE+(1-MIN_SCALE)*(1-Math.abs(position));
            page.setScaleX(scaleFactor);
            page.setScaleY(scaleFactor);
            }else{// (1,+Infinity]  
// This page is way off-screen to the right.  
            page.setAlpha(0);
            }
    }
}
